549 research outputs found
Foot and Mouth Disease Eradication in Former Czechoslovakia
In former Czechoslovakia after the Second World War foot and mouth disease (FMD) was widely spread causing enormous losses to animal production. First reliable data were from 1952 when the FMD was reported in 5,912 villages with 316,997 diseased and 23,112 dead animals. Following a very demanding anti-FMD programme, panzootic occurrence was gradually reduced to sporadic cases and finally to the eradication in 1975. During 1952-1975 there were reported 8,898 new FMD outbreaks (villages). Anti-FMD protection measures, eradication strategy and methods are described. The eradication was achieved mainly thanks to strict measures for avoiding FMD introduction from abroad, animal population health protection including FMD vaccination of threatened populations (annual ratios vaccinations/cattle population oscillated between 0.0293 in 1955 and 1.8168 in 1973 with an average of 0.6445) and timely FMD discovery followed by a rapid response applying very strict intrafocal, perifocal and territorial measures. There were used different complex methods, including stamping-out, adjusted flexibly in time and place to epizootiological situation and influencing factors such as livestock concentration in large units. Important role was played by the strong and centralized public veterinary service with adequate infrastructure, necessary facilities such as FMD diagnostic laboratory, vaccine production and rendering plants, material and financial support. During 1957-1960, a particular epizootiological research was conducted in 70 districts, 245 villages and 459 farms affected by FMD; the results were expressed in morbidity, mortality, sanitary slaughter, disease course, outbreak duration, promptness of disease detection and response, virus types and ways of transmission
Tris{N-[bis(dimethylamino)phosphinoyl]-2,2,2-trichloroacetamido}(triphenylphosphine oxide)holmium(III)
In the title compound, [Ho(C6H12Cl3N3O2P)3(C18H15OP)], the HoIII ion is surrounded by six O atoms from the three bidentate N-[bis(dimethylamino)phosphinoyl]-2,2,2-trichloroacetamido ligands (L
−) and by one O atom from the triphenylphosphine oxide ligand, with the formation of a distorted monocapped octahedron. In one ligand L
−, the trichloromethyl group is rotationally disordered between two orientations in a 1:1 ratio, while two dimethylamino groups in another ligand L
− are disordered between two conformations, each with the same 1:1 ratio
Phonon dispersion and electron-phonon interaction for YBa_2Cu_3O_7 from first-principles calculations
We present a first principles investigation of the lattice dynamics and
electron-phonon coupling of the high-T_c superconductor YBa_2Cu_3O_7 within the
framework of density functional perturbation theory using a mixed-basis
pseudopotential method. The calculated phonon dispersion curves are in
excellent agreement with Raman, infrared and neutron data. Calculation of the
Eliashberg function alpha^2F leads to a small electron-phonon coupling
lambda=0.27 in disagreement with earlier approximate treatments. Our
calculations strongly support the view that conventional electron-phonon
coupling is not an important contribution to superconductivity in high-T_c
materials.Comment: 4 pages, 4 figure
The Quadrupole Magnets for the LHC Injection Transfer Lines
Two injection transfer lines, each about 2.8 km long, are being built to transfer protons at 450 GeV from the Super Proton Synchrotron (SPS) to the Large Hadron Collider (LHC). A total of 180 quadrupole magnets are required; they are produced in the framework of the contribution of the Russian Federation to the construction of the LHC. The classical quadrupoles, built from laminated steel cores and copper coils, have a core length of 1.4 m, an inscribed diameter of 32 mm and a strength of 53.5 T/m at a current of 530 A. The total weight of one magnet is 1.1 ton. For obtaining the required field quality at the small inscribed diameter, great care in the stamping of the laminations and the assembly of quadrants is necessary. Special instruments have been developed to measure, with a precision of some mm, the variations of the pole gaps over the full length of the magnet and correlate them to the obtained field distribution. The design has been developed in a collaboration between BINP and CERN. Fabrication and the magnetic measurements are done at BINP and should be finished at the end of the year 2000
Structure optimization effects on the electronic properties of BiSrCaCuO
We present detailed first-principles calculations for the normal state
electronic properties of the high T superconductor
BiSrCaCuO, by means of the linearized augmented plane wave
(LAPW) method within the framework of density functional theory (DFT). As a
first step, the body centered tetragonal (BCT) cell has been adopted, and
optimized regarding its volume, ratio and internal atomic positions by
total energy and force minimizations. The full optimization of the BCT cell
leads to small but visible changes in the topology of the Fermi surface,
rounding the shape of CuO barrels, and causing both the BiO bands,
responsible for the pockets near the \textit{\=M} 2D symmetry point, to dip
below the Fermi level. We have then studied the influence of the distortions in
the BiO plane observed in nature by means of a
orthorhombic cell (AD-ORTH) with space group. Contrary to what has been
observed for the Bi-2201 compound, we find that for Bi-2212 the distortion does
not sensibly shift the BiO bands which retain their metallic character. As a
severe test for the considered structures we present Raman-active phonon
frequencies () and eigenvectors calculated within the frozen-phonon
approximation. Focussing on the totally symmetric A modes, we observe
that for a reliable attribution of the peaks observed in Raman experiments,
both - and a-axis vibrations must be taken into account, the latter being
activated by the in-plane orthorhombic distortion.Comment: 22 pages, 4 figure
Assessment of the application for renewal of authorisation of GalliPro ® (Bacillus subtilis DSM 17299) for chickens for fattening
GalliPro \uae is the trade name for a feed additive based on viable cells of a strain of Bacillus subtilis intended for use as a zootechnical additive (gut flora stabiliser) in feed for chickens for fattening. The product is currently authorised for use in chickens for fattening. This opinion concerns the renewal of this authorisation. Bacillus subtilis is considered by EFSA to be suitable for the qualified presumption of safety (QPS) approach to establish the safety for the target species, consumers and the environment. The identity of the strain present in the additive was established and evidence was provided on the lack of toxigenic potential as well as acquired antibiotic resistance determinants to antibiotics of human and veterinary importance. Accordingly, this strain is presumed safe for the target species, consumers of products derived from animals fed the additive and the environment. Since no concerns are expected from other components of the additive, GalliPro \uae is considered safe for the target species, consumers and the environment. The applicant has provided evidence that the additive currently in the market complies with the existing conditions of authorisation. The FEEDAP Panel confirms its previous conclusions that GalliPro \uae is safe for the target species; consumers of products from animals fed the additive and the environment. GalliPro \uae should be considered a potential respiratory sensitiser. In the absence of data, the FEEDAP Panel cannot conclude on the potential of GalliPro \uae for skin and eyes irritancy and dermal sensitisation
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